In lean times like these, it's important to get your personal finances under control. But creating a detailed budget and having the discipline and diligence to stick to it is often easier said than done. Thankfully there are plenty of apps available that can help you not only track your income and expenses, but also stash some extra cash, too.

If you need a little extra help managing of your income, bills and spending -- and with setting aside funds for a rainy day -- try one of our favorite free personal finance apps:

1. Mint

This popular, all-in-one personal finance app from Quicken maker Intuit seamlessly organizes and categorizes your income, debt and spending for you -- all in one neat, clean user interface. And for free.

Mint draws data directly from all of your financial accounts, including your personal bank, retirement, college loan and credit card accounts. Then it tells you what you owe to whom, in real-time. It also generates individualized payment and savings plans to help you reach your financial goals.

Mint can be a smart choice for busy people who don't have the time to manually, meticulously enter each and every one of their financial transactions. It automatically tracks and categorizes your activity in each of the accounts you give it permission to sync up with, making it easier to build -- and hopefully adhere to -- a realistic budget. With Mint, you know your average spending in any category (entertainment, investments, bills, health and fitness, etc.). You can also instantly compare your spending month-to-month and year-to-year to gauge how well you're sticking to your budget.

2. Expensify

Tallying up business expenses can be tricky and tedious. Expensify simplifies this often frustrating, time-sucking process by creating organized expense reports for you for free. The sleek, graph-loaded app lets you manage business travel plans, complete with real-time flight status updates, automatically track mileage via GPS and even log and bill time worked to clients.

Expensify also nixes the need to hang on to paper receipts. Its SmartScan feature lets you securely store and categorize printed receipts by snapping photos of them with your smartphone or tablet camera. Transactions of $75 and less auto generate IRS-guaranteed eReciepts.

One of the most useful features is SmartReports, which auto-magically fills out annoying Excel spreadsheets for you, with applicable digital receipts conveniently attached.

Expensify is available for Android, BlackBerry, iPhone, iPad and Windows Phone.

3. SmartyPig

Like its piggy bank-inspired name implies, SmartyPig helps you save money. There's only one catch -- you have to open a free, FDIC-insured SmartyPig savings account. Luckily they're free, just like the app, which lets you save for things you want, like perhaps a house, a car or a vacation. Add money to your savings goals whenever you want right from your phone or tablet.

You'll need to link up an existing bank or credit union savings or checking account to siphon funds to your SmartyPig account from. Create as many SmartyPig savings goals as you want, then use the app's social sharing function to spread the word on Facebook and Twitter. Interest rates for SmartyPig on balances between $0 and $50,000 earn 0.995 percent (one percent annual percentage yield).